The present invention relates to a web layering device of the type including a plurality of sequentially disposed individual layering tables, or carriages, mounted to undergo back and forth movement, a stationary feed unit cooperating with the first layering table in the sequence, and a removal unit associated with a transporting unit for the web.
In known web layering units including individual layering tables, i.e., layering tables having single layering belts, the speed at which the web can be conveyed is limited to 40 to 60 m/min, depending on the fineness of the fiber material involved. At higher conveying speeds, the web will in part be lifted away from the layering tables, under the influence of an air stream produced by movement of the tables, so that the formation of wrinkles is possible.
In the case of ribbon layers, the web is guided between two sheets moved in the same direction so that no danger of lifting exists and consequently a higher production speed is possible. However, the drawback of the ribbon layers is, in particular, that the web is bunched at the points of direction reversal of the sheets and consequently is wrinkled, particularly if fine fiber material is involved. A further drawback of this type of device is that it affords poor accessibility on the occasion of malfunctions, for example when overlapping of the web occurs.